The alert came the wake of a March 21 fire that killed four group home residents in the Adirondack town of Wells, and is a possible signal concerning the cause of the blaze.

The June 23 internal memo "was part of a series of actions that OMRDD took directly after the fire," said agency spokesman Herm Hill, adding it was to reinforce a policy already in place.

The timing of the memo, which came out less than two weeks after a report by the state Office of Fire Control and Prevention found the blaze stemmed from "human action," suggests a possible cause was unsafe smoking, either by a worker or a resident of the Riverview home.

A final report on the fire, however, is being withheld by State Police pending a Hamilton County grand jury investigation.

"There is a potential for criminal investigation," Hill said, explaining one reason why the final report hasn't been released.

The Office of Fire Prevention found problems with the group home, which had been constructed less than a year before the fire. There were questions about whether the building had an adequate sprinkler system, and investigators found that the alarm system was set up so that the staff, and not the local fire department, was the first to be called when an alarm went off.

Workers at the home may have falsified fire drill reports, according to an internal OMRDD report released earlier this summer by the state Civil Liberties Union.

In May, OMRDD announced the formation of a blue-ribbon panel to recommend ways to improve fire safety at its facilities.

If the fire did result from a burning cigarette butt, it might have been from someone smoking on the structure's porch area. There was at least 2 feet of snow on the ground at the time of the blaze, said Wells Supervisor Brian Towers.

Towers said he had also been told that one of the recent residents in the home was a smoker, although state officials couldn't immediately confirm that. Some of the employees who worked at different shifts in the home may also have smoked.

Nine disabled people lived at Riverview, including several who had previously been in the now-closed Willowbrook facility on Staten Island.

Towers noted that the one-story structure, with some of the walls still partially standing, has remained untouched since the fire. It's behind a chain-link fence and remains under round-the-clock guard.

"The whole thing is still sitting there just the way we left it" the night of the fire, Towers said.